I am wondering whether Filter can be used to filter a range, e.g. group category id range from 100 to 200. I went through the Filter chapter in Hibernate Search in Action, but couldn't get this. Thanks in advance.

Sorry for my stupid post. I read the Hibernate Search in Action about two months ago. Now, when I tried to use it, I also most forgot what I read.
BTW, I found a very important link for discuss which range filter and range query is fastest. It deserve reading. http://wiki.apache.org/jakarta-lucene/FilteringOptions